Rockwool is a synthetic product used in propagation and hydroponic production systems. It is light weight, sterile and provides a good balance between water holding capacity and air porosity.

Rockwool holds more water than some other media components, but is a popular media for hydroponics.

It comes in preformed blocks or loose to mix to be mixed with other media components.

Photo of rockwool in preformed blocks. Photo of a loose pile of rockwool.